Results 31 to 40 of about 217,791 (313)
Full one-loop amplitudes from tree amplitudes [PDF]
We establish an efficient polynomial-complexity algorithm for one-loop calculations, based on generalized $D$-dimensional unitarity. It allows automated computations of both cut-constructible {\it and} rational parts of one-loop scattering amplitudes ...
+21 more
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On the Cuts of Scattering Amplitudes [PDF]
The use of complex analysis for computing one-loop scattering amplitudes is naturally induced by generalised unitarity-cut conditions, fulfilled by complex values of the loop variable. We report on two techniques: the cut-integration with spinor-variables as contour integrals of rational functions; and the use of the Discrete Fourier Transform to ...
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Tropical fans, scattering equations and amplitudes
We describe a family of tropical fans related to Grassmannian cluster algebras. These fans are related to the kinematic space of massless scattering processes in a number of ways.
James Drummond+3 more
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ANALYTIC SCATTERING AMPLITUDES FOR QCD [PDF]
By analytically continuing QCD scattering amplitudes through specific complexified momenta, one can study and learn about the nature and the consequences of factorization and unitarity. In some cases, when coupled with the largest time equation and gauge invariance requirement, this approach leads to recursion relations, which greatly simplify the ...
Diana Vaman, York-Peng Yao
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Massive on-shell supersymmetric scattering amplitudes
We introduce a manifestly little group covariant on-shell superspace for massive particles in four dimensions using the massive spinor helicity formalism.
Aidan Herderschee+2 more
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Soft radiation from scattering amplitudes revisited
We apply the recently developed formalism by Kosower, Maybee and O’Connell (KMOC) [12] to analyse the soft electromagnetic and soft gravitational radiation emitted by particles without spin in D ≥ 4 dimensions.
A. Manu+3 more
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Scatterings of Massive String States from D-brane and Their Linear Relations at High Energies [PDF]
We study scatterings of bosonic massive closed string states at arbitrary mass levels from D-brane. We discover that all the scattering amplitudes can be expressed in terms of the generalized hypergeometric function with special arguments, which ...
Bachas+38 more
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Pion-pion scattering amplitude [PDF]
We obtain reliable ππ scattering amplitudes consistent with experimental data, both at low and high energies, and fulfilling appropriate analyticity properties. We do this by first fitting experimental low energy [s^(1/2) ≤ (1.42 GeV] phase shifts and inelasticities with expressions that incorporate analyticity and unitarity.
Peláez Sagredo, José Ramón+1 more
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Automating scattering amplitudes with chirality flow
Recently we introduced the chirality-flow formalism, a method which builds on the spinor-helicity formalism and is inspired by the color-flow idea in QCD.
Andrew Lifson+2 more
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Scattering amplitudes in Lifshitz spacetime [PDF]
We consider the calculation of scattering amplitudes in field theories dual to Lifshitz spacetimes. These amplitudes provide an interesting probe of the IR structure of the field theory; our aim is to use them to explore the observable consequences of the singularity in the spacetime.
Andrade, T., Ross, Simon F., Lei, Y.
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